In the overhead control panel on my 07 S550 I found a Red 14 GA wire that is hot all the time and a Grey wire on the "K" connector that is hot in switch position 2. Great but it only has 7 volts DC on it.. Anybody know what that connector goes to? I am thinking of using a small relay with the coil operated by that 7 volt signal to switch the power to the radar detector. Looks like a bad deal to run a wire up the pillar as there is air bags in there..Any good ideas?